Me and my friend together bought two A700EX from my local hobby shop early July, and since day 1 I've asked the hobby shop, who stock no parts for the A700, to order the gear diff upgrades ST23 ST26 and the metal gears. Now two months down the road, all I got are just promises that they would come some day.

During these times one car already ran but the first day it clipped a sidewall, the drive cup popped and the plastic gears shredded. As the parts are not yet arrived, I tried to make shift by using Spec R gears, coupled by your recommended modifications, including adding shims and putting a plastic stick to hold the drive cup. On the second day, the drive cup again popped, this time before the car even finish half the battery. The second car is still in the box, unassembled, just don't want to cannibalize it for parts, and even if we do, the gear just won't last for long anyway.

Frankly I am really disappointed on the gear diff design, it just ruined the whole car design. There was just nothing to hold the drive cup except for that flimsy o-ring, which is inadequate for today's high power motors. Couple with the extraordinary design of the car overall I would expect a more foolproof diff design, maybe with the ST23 and ST26 comes standard, or just make the shaft of the ST07 drive cup longer so that a pin could be used to hold it in place instead of having the ST20. I still remember when the car first ran it was so good, until the gear diff failed, it just ruined the whole experience. I tried things to revive the car, fix the gear diff, short of asking a machine shop to custom made two drive cups that could be pinned.

Anyway, I would be highly appreciated if you could check whether you received any orders from Hong Kong, and if so please ship that out ASAP. If there has been no orders from Hong Kong please pm me, I would have a word with my hobby shop and would order from you direct instead. Its just a shame for the car to sit gathering dust.

Me and my friend together bought two A700EX from my local hobby shop early July, and since day 1 I've asked the hobby shop, who stock no parts for the A700, to order the gear diff upgrades ST23 ST26 and the metal gears. Now two months down the road, all I got are just promises that they would come some day.

During these times one car already ran but the first day it clipped a sidewall, the drive cup popped and the plastic gears shredded. As the parts are not yet arrived, I tried to make shift by using Spec R gears, coupled by your recommended modifications, including adding shims and putting a plastic stick to hold the drive cup. On the second day, the drive cup again popped, this time before the car even finish half the battery. The second car is still in the box, unassembled, just don't want to cannibalize it for parts, and even if we do, the gear just won't last for long anyway.

Frankly I am really disappointed on the gear diff design, it just ruined the whole car design. There was just nothing to hold the drive cup except for that flimsy o-ring, which is inadequate for today's high power motors. Couple with the extraordinary design of the car overall I would expect a more foolproof diff design, maybe with the ST23 and ST26 comes standard, or just make the shaft of the ST07 drive cup longer so that a pin could be used to hold it in place instead of having the ST20. I still remember when the car first ran it was so good, until the gear diff failed, it just ruined the whole experience. I tried things to revive the car, fix the gear diff, short of asking a machine shop to custom made two drive cups that could be pinned.

Anyway, I would be highly appreciated if you could check whether you received any orders from Hong Kong, and if so please ship that out ASAP. If there has been no orders from Hong Kong please pm me, I would have a word with my hobby shop and would order from you direct instead. Its just a shame for the car to sit gathering dust.

Thank you for your attention.

Regards,

Jason

I think you probably built the diff wrong! The diff is a work of art! Both me and my dad have been running the car for the past two years and have never had a problem with the diffs! And my dad tests the durability of cars alot! Lol

....Frankly I am really disappointed on the gear diff design, it just ruined the whole car design. There was just nothing to hold the drive cup except for that flimsy o-ring, which is inadequate for today's high power motors. Couple with the extraordinary design of the car overall I would expect a more foolproof diff design, maybe with the ST23 and ST26 comes standard, or just make the shaft of the ST07 drive cup longer so that a pin could be used to hold it in place instead of having the ST20. I still remember when the car first ran it was so good, until the gear diff failed, it just ruined the whole experience. I tried things to revive the car, fix the gear diff, short of asking a machine shop to custom made two drive cups that could be pinned.
Anyway, I would be highly appreciated if you could check whether you received any orders from Hong Kong, and if so please ship that out ASAP. If there has been no orders from Hong Kong please pm me, I would have a word with my hobby shop and would order from you direct instead. Its just a shame for the car to sit gathering dust.
Thank you for your attention.
Regards,
Jason

Over filling the gear diff will put pressure on the out drives and possibly cause them to pop out. If you look at the manual and fill the diff per Oleg's instructions you will not have problems. I've had my car now about 6 weeks and have probably ran about 4000 laps. Not once have the out drives popped out and I've had some very high G traction roles.

As for the plastic gears, yes there are some mods that need to be made in order to make them last. Either file the top ST20 that protrudes through the main gear so it's flat with the top of G05 and than places 3-4 .1mm shims between B85 and OR05 to push the gear up.

Or what I've done is just cut small paper shims from card stock that's used as part of the packaging on parts you buy for the car. Cut to the size of the small slots on the G05 gear. I usually put 2 in each slot, approx .5mm. This pushes the main gear up towards the planetary gears so they mesh together better. If done on new gears they should last a long time.

Me and my friend together bought two A700EX from my local hobby shop early July, and since day 1 I've asked the hobby shop, who stock no parts for the A700, to order the gear diff upgrades ST23 ST26 and the metal gears. Now two months down the road, all I got are just promises that they would come some day.

During these times one car already ran but the first day it clipped a sidewall, the drive cup popped and the plastic gears shredded. As the parts are not yet arrived, I tried to make shift by using Spec R gears, coupled by your recommended modifications, including adding shims and putting a plastic stick to hold the drive cup. On the second day, the drive cup again popped, this time before the car even finish half the battery. The second car is still in the box, unassembled, just don't want to cannibalize it for parts, and even if we do, the gear just won't last for long anyway.

Frankly I am really disappointed on the gear diff design, it just ruined the whole car design. There was just nothing to hold the drive cup except for that flimsy o-ring, which is inadequate for today's high power motors. Couple with the extraordinary design of the car overall I would expect a more foolproof diff design, maybe with the ST23 and ST26 comes standard, or just make the shaft of the ST07 drive cup longer so that a pin could be used to hold it in place instead of having the ST20. I still remember when the car first ran it was so good, until the gear diff failed, it just ruined the whole experience. I tried things to revive the car, fix the gear diff, short of asking a machine shop to custom made two drive cups that could be pinned.

Anyway, I would be highly appreciated if you could check whether you received any orders from Hong Kong, and if so please ship that out ASAP. If there has been no orders from Hong Kong please pm me, I would have a word with my hobby shop and would order from you direct instead. Its just a shame for the car to sit gathering dust.

Thank you for your attention.

Regards,

Jason

Dear Jason

How may I help you and your friend in anyway?
You may contact me through my mail or pm me.
Over filling seems like the cause for diff half to pop out
Here is the step by step how to fill up the diff
1. assemble the diff and fill up the oil (dont worry about over filling at this step)
2. tighten the assembly, leave AT24 face up and not to insert ST07 on this end
3. heat the unit to operating tempeture (around 60' C usually work for me)
4. after the excess fluid comes out from the AT24 then clean it.
5. insert ST07 into the place slowly, more excess fluid may still come out.
6. pull out ST07 and repeat step 5 as needed.
7. Put two orings into ST07 or the trick Oleg mention before.

Now you have a diff complet with proper fluid level, this trick works with all other cars as well.
If you have time you can use vacumm pump that we use for shocks, try to pump the air out before step 4.

I hope this will help you to have more track time before your new parts arrives.

Me and my friend together bought two A700EX from my local hobby shop early July, and since day 1 I've asked the hobby shop, who stock no parts for the A700, to order the gear diff upgrades ST23 ST26 and the metal gears. Now two months down the road, all I got are just promises that they would come some day.

During these times one car already ran but the first day it clipped a sidewall, the drive cup popped and the plastic gears shredded. As the parts are not yet arrived, I tried to make shift by using Spec R gears, coupled by your recommended modifications, including adding shims and putting a plastic stick to hold the drive cup. On the second day, the drive cup again popped, this time before the car even finish half the battery. The second car is still in the box, unassembled, just don't want to cannibalize it for parts, and even if we do, the gear just won't last for long anyway.

Frankly I am really disappointed on the gear diff design, it just ruined the whole car design. There was just nothing to hold the drive cup except for that flimsy o-ring, which is inadequate for today's high power motors. Couple with the extraordinary design of the car overall I would expect a more foolproof diff design, maybe with the ST23 and ST26 comes standard, or just make the shaft of the ST07 drive cup longer so that a pin could be used to hold it in place instead of having the ST20. I still remember when the car first ran it was so good, until the gear diff failed, it just ruined the whole experience. I tried things to revive the car, fix the gear diff, short of asking a machine shop to custom made two drive cups that could be pinned.

Anyway, I would be highly appreciated if you could check whether you received any orders from Hong Kong, and if so please ship that out ASAP. If there has been no orders from Hong Kong please pm me, I would have a word with my hobby shop and would order from you direct instead. Its just a shame for the car to sit gathering dust.

Thanks very much everyone for the reply and support. Today I went to the hobby shop and ask again, the owner said he is chasing up my order. Shall see how that goes in a few days and would keep Oleg, Wen and Angus posted. Meanwhile I shall communicate with Wen and Angus by pm. Thanks again for the response!